INFO: task syz.2.467:9036 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.467 state:D stack:25864 pid:9036 ppid:8654 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747 open_dummy_log fs/jfs/jfs_logmgr.c:1191 [inline] lmLogOpen+0x1af/0xfb0 fs/jfs/jfs_logmgr.c:1066 jfs_mount_rw+0xea/0x670 fs/jfs/jfs_mount.c:257 jfs_fill_super+0x592/0xac0 fs/jfs/super.c:565 mount_bdev+0x22b/0x2d0 fs/super.c:1643 legacy_get_tree+0xea/0x180 fs/fs_context.c:662 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3377 do_mount fs/namespace.c:3717 [inline] __do_sys_mount fs/namespace.c:3926 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3903 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f8c6e39038a RSP: 002b:00007f8c6f2b6e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f8c6f2b6ef0 RCX: 00007f8c6e39038a RDX: 00002000000001c0 RSI: 0000200000000180 RDI: 00007f8c6f2b6eb0 RBP: 00002000000001c0 R08: 00007f8c6f2b6ef0 R09: 0000000000000002 R10: 0000000000000002 R11: 0000000000000246 R12: 0000200000000180 R13: 00007f8c6f2b6eb0 R14: 0000000000006188 R15: 00002000000009c0 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by kworker/u4:7/2872: 2 locks held by getty/5548: #0: ffff88814cad60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 3 locks held by kworker/0:4/5854: #0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900048efd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900048efd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff88805eb87240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26c/0x3170 drivers/net/netdevsim/fib.c:1491 2 locks held by syz-executor/6846: #0: ffff88801f7ec0e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88801f7ec0e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88801f7ec0e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8312: #0: ffff88801eaf40e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88801eaf40e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88801eaf40e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8357: #0: ffff88807dfd80e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807dfd80e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807dfd80e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8575: #0: ffff888079e580e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff888079e580e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888079e580e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8790: #0: ffff888040b880e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff888040b880e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888040b880e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz.2.467/9036: #0: ffff88807cb960e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807cb960e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807cb960e0 (&type->s_umount_key#58){++++}-{3:3}, at: mount_bdev+0x1e8/0x2d0 fs/super.c:1641 #1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: open_dummy_log fs/jfs/jfs_logmgr.c:1191 [inline] #1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogOpen+0x1af/0xfb0 fs/jfs/jfs_logmgr.c:1066 2 locks held by syz-executor/9233: #0: ffff888020eae0e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff888020eae0e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888020eae0e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/11168: #0: ffffffff8dfbc488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff8dfbc488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472 #1: ffffffff8cd35bf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #1: ffffffff8cd35bf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5854 Comm: kworker/0:4 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events kfree_rcu_work RIP: 0010:unwind_done arch/x86/include/asm/unwind.h:50 [inline] RIP: 0010:unwind_next_frame+0xa6/0x2970 arch/x86/kernel/unwind_orc.c:475 Code: 00 00 4c 89 e3 48 c1 eb 03 42 0f b6 04 2b 84 c0 0f 85 df 21 00 00 41 8b 2c 24 31 ff 89 ee e8 f1 ef 4a 00 89 ac 24 8c 00 00 00 <85> ed 74 77 4c 89 74 24 60 48 89 5c 24 18 bf 01 00 00 00 e8 72 c6 RSP: 0018:ffffc900048ef4f8 EFLAGS: 00000293 RAX: ffffffff813aa35f RBX: 1ffff9200091deb9 RCX: 0000000000000000 RDX: ffff88805e665a00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffc900048ef690 R09: 0000000000000005 R10: 0000000000000004 R11: 0000000000000000 R12: ffffc900048ef5c8 R13: dffffc0000000000 R14: ffffc900048ef600 R15: ffffffff8171580b FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555564405c8 CR3: 000000003d9b7000 CR4: 00000000003506f0 Call Trace: arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] kmem_cache_free_bulk+0x347/0x460 mm/slub.c:3934 kfree_bulk include/linux/slab.h:517 [inline] kvfree_rcu_bulk+0x1eb/0x470 kernel/rcu/tree.c:3032 kfree_rcu_work+0x32f/0x3a0 kernel/rcu/tree.c:3111 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293